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Merrimack River
Merrimack River Current Water Temperature and Forecast
On this page, you will find comprehensive information about the water temperature in Merrimack River, including current readings, historical data and trends, monthly averages, as well as weather forecasts and upcoming temperature predictions. We find every spot where you can swim and tell you what the water temperature is there today and throughout the year.
Current Water Temperature in Merrimack River
59°F
TODAY
59°F
YESTERDAY
59°F
A WEEK AGO
As of today, the minimum water temperature in the Merrimack River ranges from 54°F (12°C) to 60°F (15°C). The water is significantly warmer, and swimming becomes possible for most people. However, caution may still be required for prolonged stays in the water, as extended exposure can cause discomfort. This is a suitable temperature range for short swims and for those accustomed to cooler water. For more comfortable swimming, it is recommended to use proper gear.
It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Analysis, Historical Data, and Forecast of Water Temperature
Water Temperature Chart for Merrimack River Over the Last 30 Days
Today the water temperature in Merrimack River is higher than the same day in previous years. The water temperature range here in May is from 46°F to 70°F. The water temperature has decreased over the past 7 days but has increased over the past month.
The forecasted water temperature values for Merrimack River are presented in the table below.
The actual water temperature values near the shore may differ by a few degrees from the stated values. For the development of the forecast, we use our own mathematical model that takes into account the current water temperature changes, historical data, and key weather trends, including wind strength and direction, and air temperature in each specific region.
Daily Water Temperature Chart
| Date | Current | Average | Forecast |
|---|---|---|---|
| May 3 | 59°F | 56°F | |
| May 4 | 59°F | 56°F | |
| May 5 | 60°F | 56°F | |
| May 6 | 59°F | 56°F | |
| May 7 | 60°F | 56°F | |
| May 8 | 60°F | 56°F | |
| May 9 | 59°F | 56°F | |
| May 10 | 59°F | 56°F | |
| May 11 | 56°F | 59°F | |
| May 12 | 56°F | 59°F | |
| May 13 | 56°F | 58°F | |
| May 14 | 56°F | 58°F | |
| May 15 | 56°F | 58°F | |
| May 16 | 56°F | 58°F | |
| May 17 | 56°F | 58°F | |
| May 18 | 56°F | 58°F |
Water Temperature Ranges in Merrimack River by Month
January
| Minimum | Average | Maximum |
|---|---|---|
| 32°F | 40°F | 48°F |
February
| Minimum | Average | Maximum |
|---|---|---|
| 32°F | 40°F | 48°F |
March
| Minimum | Average | Maximum |
|---|---|---|
| 32°F | 42°F | 52°F |
April
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 49°F | 61°F |
May
| Minimum | Average | Maximum |
|---|---|---|
| 46°F | 56°F | 70°F |
June
| Minimum | Average | Maximum |
|---|---|---|
| 57°F | 65°F | 72°F |
July
| Minimum | Average | Maximum |
|---|---|---|
| 63°F | 68°F | 75°F |
August
| Minimum | Average | Maximum |
|---|---|---|
| 63°F | 71°F | 73°F |
September
| Minimum | Average | Maximum |
|---|---|---|
| 52°F | 64°F | 66°F |
October
| Minimum | Average | Maximum |
|---|---|---|
| 46°F | 56°F | 61°F |
November
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 47°F | 61°F |
December
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 40°F | 46°F |
Monthly Water Temperature Histogram for Merrimack River
Water Temperature in Cities and Towns on Merrimack River
Merrimack River Weather
MAY 10
45°F / 57°F
moderate rainrain: 85% | wind: 17 mph
MAY 11
45°F / 63°F
clear skyrain: 35% | wind: 14 mph
MAY 12
37°F / 73°F
overcastrain: 1% | wind: 11 mph
MAY 13
52°F / 77°F
overcastrain: 1% | wind: 9 mph
MAY 14
57°F / 64°F
light drizzlerain: 11% | wind: 5 mph
Water Temperature in Merrimack River: General Trends and Swimming Opportunities
Source Pemigewasset River-Winnipesaukee River juncture
• location: Franklin, Merrimack County, New Hampshire
Mouth Gulf of Maine
• location Newburyport, Essex County, Massachusetts
Length 117 mi (188 km)
The Merrimack River, which flows through New Hampshire and Massachusetts, is one of the largest rivers in the northeastern United States. The water temperature in the Merrimack River varies throughout the year, with cooler temperatures in the spring and fall, often ranging from 40°F to 55°F (4°C to 13°C). In the summer months, the water warms up to more comfortable temperatures, typically ranging between 60°F and 75°F (15°C to 24°C), making it more suitable for swimming.
Swimming in the Merrimack River is possible, particularly in areas with slower-moving water or designated recreational zones. Some parts of the river, especially around cities like Lowell and Lawrence, offer public access points where people can swim or relax by the water. However, caution is recommended, as the river's current can be strong in certain sections, and water quality can fluctuate, especially after heavy rainfall. While swimming isn't the most common activity in the Merrimack, it remains an option for those looking to cool off during the summer months. The river is also popular for boating, fishing, and kayaking, attracting a wide range of water enthusiasts.
Geographical Location of Merrimack River
Nearby Rivers
Frequently Asked Questions About Merrimack River and its Water Temperatures
What is the current water temperature in Merrimack River?
The water temperature today in Merrimack River ranges from 55°F (12.7°C) to 66°F (18.8°C).
What is the water temperature in Merrimack River during the summer months?
The average water temperature in Merrimack River during the summer months is typically between 65°F to 71°F (19°C to 21°C), and it can reach up to 75°F (24°C) at its warmest. However, in some years, the temperature may exceed this range.
What is the water temperature in Merrimack River in May?
The average water temperature in Merrimack River in May ranges from 46°F to 70°F (8°C to 21°C).
What is the water temperature in Merrimack River in September?
The average water temperature in Merrimack River in September is typically between 52°F to 66°F (11°C to 19°C).
Where does Merrimack River flow?
Merrimack River flows through United States (New Hampshire, Massachusetts).
Is it possible to swim in the Merrimack River?
Yes, it is possible to swim in the Merrimack River. However, safety and current conditions should always be checked prior to swimming due to occasional pollution issues.
What major cities are located on Merrimack River?
Cities along the course of Merrimack River include Concord (New Hampshire), Haverhill (Massachusetts), Lawrence (Massachusetts), Lowell (Massachusetts), Manchester (New Hampshire), Nashua (New Hampshire).